The UN human rights chief has called for an international investigation of rights abuses and violence in Yemen's civil war, which has killed thousands of people.

Zeid Ra'ad al-Hussein insisted that a domestic panel set up to look into violations has not been up to the task.

The call came as his Geneva office released a 22-page report chronicling abuses on both sides in the conflict, which pits the internationally recognised Yemeni government, backed by a Saudi-led coalition, against Shiite rebels known as Houthis and their allies.

In a statement, Mr Zeid's office said he called on the international community to establish an international, independent body to carry out comprehensive investigations in Yemen, noting in particularly challenges faced by the national panel set up under President Abed Rabbo Mansour Hadi - notably, security concerns.

Mohammad Ali Alnsour, who heads the Middle East and North Africa section of the UN Human Rights office, said a recent report by the national panel focused on alleged violations by the Houthis, and said a "more objective, more comprehensive" report of rights violations by all sides was needed.

"Unfortunately, the humanitarian situation in Yemen is very bad," he told reporters.

Mr Zeid, who is also a member of the Jordanian royal family, did not specify who would set up the international body, but he is expected to present the report's findings to the UN Human Rights Council at its session next month.

Last year, the council passed a resolution - brought by Saudi Arabia and allies - that deferred to national investigators to report on rights abuses.

Fighting in Yemen escalated in March 2015 with the start of Saudi-led air strikes targeting the Houthis. Mr Zeid's office says an estimated 3,799 civilians have been killed since then. The UN and rights groups estimate at least 9,000 people overall have died. Some 3 million people have also been displaced inside the Arab world's poorest country.

The report by the UN rights office also denounced the recruitment of child fighters in Yemen, civilian casualties linked to suspected US drone strikes that target al Qaida's local branch, attacks on human rights defenders and a crackdown on freedom of expression.

Last week, the aid group Doctors Without Borders announced a pull-out from northern Yemen following an air strike against a hospital it supported there - the fourth such deadly attack on one of its medical facilities in the war.